1. What is the tissue that secretes cerebrospinal fluid in the ventricles?
2. In explaining fluorescence, why is the emission a longer wavelength than
energy is lost before a hoton is re-emitted
3. In the knee-jerk reflex, answer either (1) Where is the cell body of
the motor neuron? or (2) Where is the cell body of the sensory neuron?
ventral horn in gray matter of spinal cord, in dorsal root ganglion PNS
4. "Your patient is having a stroke. Quick! Give him some TPA."
Under what circumstances would tissue plasminogen activator be contraindicated?
5. Confocal microscope. Answer either (1) How did they make tau look red
and tubulin look green in that textbook micrograph? or (2) What property
of the technology allowed Dr Stark's student make a Quicktime movie focusing
through the depth of the Drosophila retina?
bind green- or red-emitting fluorophores to secondary antibody that binds
primary antibody to tau and tubulin, optical sectioning = low depth of focus
6. "Histochemical fluorescence." What substance was seen in the
fluorescence microscope when the tract from the substantia nigra to the
striatum (basal ganglia) was visualized?
dopamine combined with formaldehyde
7. "Fluorescent- or gold-labeled secondary body." Answer either
(1) What specific molecule does it bind to? or (2) Why gold? (referring
primary antibody, electron dense
8. Say something about a structural specialization on the postsynaptic dendrite
or on the postsynaptic membrane.
spine, postsynaptic density, receptors
9. Keeping in mind what I have said about techniques, what are you actually
seeing when you refer to the electron density of a membrane or a synaptic
electron dense heavy metals bound to membrane or vesicle contents
10. Give the name of a protein involved in axon transport.
tau kinesin, microtubular protein
11. In the neurons and glia lecture, we referred to two components of the
blood brain barrier between the blood and the cerebrospinal fluid. Identify
one of these.
capillary endothelium plus astrocyte end foor
12. Using a radioactive label, we can see where that radioactivity gets
to in the brain. Name (or describe) that technique.
autoradiography, expose photographic film to histological brain slice
13. Identify a protein that would be found at or near the node of Ranvier
but would not be foune (or would be found in much lesser amount) on or near
the axon under the myelin.
sodium channels, OMgp=oligodendrocyte glycoprotein
14. Why would you expect membrane to have very high resistance?
except for channels, the hydrophobic milieu of fatty acids of the bilayer
of phospholipids would not conduct ions
15. "Multiple sclerosis is an autoimmune disease." Answer either
(1) To what protein? or (2) How can you get immune to a protein that belongs
in your body?
myelin basic protein, its sequestration from immune surveillance has been
16. An action potential is (1) all-or-none, (2) non-decremental, and (3)
in the direction of making the inside of the cell more positive. Pick one
of those three attributes and say how a synaptic potential differs if it
potentials can add to each other, they get smaller with distance, they may
also be hyperpolarizing
17. "Cole and Curtis's bridge went out of balance." What did we
learn from their 1939 work on the squid giant axon with the Wheatstone bridge?
conductance goes up as the action potential passes
18. "A square wave of current injection led to a hyperpolarization
that was low pass filtered." That different shape was because of what
property of the membrane?
19. In the Goldman equation, concentrations (in and out) of sodium, potassium
and chloride, and permeabilities for all three ions, are shown. There is
an equivalent circuit (with electrical components) for the Goldman equation.
What is used in the circuit model for the sodium permeability? Be thorough
enough in your answer to address what happens to sodium permeability during
the action potential.
a variable resistor (potentiometer) that lets sodium permeability go up
20. Current flows through (what?) in the patch clamp technique that earned
Neher and Sackman the 1991 Nobel Prize.
21. Ouabain is applied to the cell. Answer either (1) Why does the membrane
potential change by a few mV? or (2) Why doesn't the membrane potential
go away right away?
3 sodiums to 2 potassiums make the pump electrogenic, otherwise potentials
are based on huge reservoirs of ion gradients that would run down very slowly
if the pump were blocked
22. In Hodgkin and Keyne's1955 experiment, what happened to the efflux of
radioactive sodium mediated by the "sodium pump" when extracellular
potassium, already low, was really lowered?
it decreased sharply because sodium transport relies on exchange with potassium
23. Discussing passive spread of a decremental potential, the current spreading
down the axoplasm gets smaller with distance from a place where a stimulus
is applied. What happened to the current that was no longer going down the
it leaked through the axon membrane's resistance and capacitance
24. What does the space constant and the time constant have to do with why
squids have giant axons?
cable equation's space constant varies with the square root of the radius
while the time constant is independent of the radius, and the space constant
over the time constant of passive spread ought to predict the action potential
25. Loss of what hormone, from an adrenalectomy, would make a rat crave
26. The lecture and figures refer to a sodium channel that is about to be
depolarized to threshold by an upstream action potential as "closed."
Right after the action potential has passed, what term do we use to describe
the status of the sodium channel?
27. Why would long QT syndrome limit a person's ability to respond to stress?
inability to have shorter action potential in the ventricualr myocardium
would limit how fast the pulse can get
28. Why, when the voltage of the squid giant axon is clamped at +65 mV (inside
positive), does the early current flow out instead of in?
despite the fact that sodium is going up against its ion gradient, the driving
potential, the voltage minus the sodium equilibrium potential, would drive
current that direction
29. A family of "I-T curves" were used by Hodgkin and Huxley to
generate two "I-V curves." Say something about these curves.
the "family" was for different voltage clamp levels, giving the
V on tie I-V curves. early and late times were chosen tor the two I-V curves.
the early curve showed the negative conductance region representing the
soduim channel activation
30. "The space clamp meant that voltage clamping was done along the
whole axon." Why would this be more useful than firing a real action
realistic (measurable, not infinitessimal) currentscould be measured
31. How much current should be carried by sodium at the sodium equilibrium
32. What are the differences in how four components form a channel for Shaker
4 proteins for shaker, 4 domains of one protein in electrophorus
33. At one time they thought that the positively charged amino acids in
S4 lined the channel, but eventually they agreed that S4 did (what?)?
sensed toe voltage for gating to cause a conformational change for activation
34. Why would pheochromocytoma cells be a reasonable model for studying
can culture adrenal medulla cancer cells which release catecholamines
35. "Ramon y Cajal's 'cell theory' implies that something like a chemical
synapse MUST exist (even though they has not been demonstrated yet)"
the alternate, Golgi's reticular theory, has continuous processes, while
separate cells require communication between cells
36. Describe the structural or molecular specializations that form an "electrical
in gap junction, connexons are formed from hexamers of connexins in register
from one cell to the next
37. "There are no inhibitory neuromuscular junctions in the vertebrate."
What does that information tell us about "the final common pathway
in the integrative action of the nervous system?"
it must be in the spinal motor neuron since there is no integration after
38. What kind of technique would be needed to determine the reversal potentials
for the IPSP and the EPSP?
39. Activation of the nerve elicited (what? - be specific) at the end plate
when Katz decreased the extracellular calcium ion concentration.
miniature end plate potentials, 0, 1, 2, or 3 of them
40. Describe either the freeze-fracture or the transmission electron microscope
image of a vesicle in the process of release.
holes (pits), omega figures
41. Why would there be transporter molecules in the vesicle membrane?
to maintain a steep gradient against leakage
42. On the spinal motor neuron, there are synapses onto the dendrites and
cell body. A picture was shown of the first synaptic area behind the Drosophila
compound eye, and the point was made that invertebrate neuropils we would
see later in the semester are similarly organized. How does this synaptic
organization differ from that of the vertebrate?
the cell body of the postsynaptic neuron is on the outside of the ganglion,
aloof from synapses
43. How could Shibire mutants have temperature sensitive paralysis when
the mutation does not block vesicle release?
it blocks recycling of vesicle membrane
44. Why would a doctor give a patient a clostridial protease that cleaves
cosmetic dermatologists would discourage wrinkles in the face by blocking
45. What is the target membrane that the vesicle-SNARE latches onto?
46. How is Met-enkephalin produced from pre-proenkephalin A?
it is cleaved from the larger protein
47. Blocking the muscarinic cholinergic receptor on the heart with atropine
would save your life if you were poisoned with what class of molecules?
48. How is a norepinephrine breakdown enzyme an important target in the
pharmacology of treatment for depression?
norepinephrine is obviously an "upper", so potentiating its action
by inhibiting its breakdown would certainly be uplifting
49. "The nicotinic receptor is ionotropic." Translate: What is
the transmitter? What is the molecular structure of the receptor? (Answer
acetylcholine gates a channel
50. While administering Prozac to a patient with depression, the doctor
needs to closely monitor (what?).
any suicidal thoughts or actions
51. In order to produce hamsters with large vs small testes, what did the
lab prep technician need to do ahead of time?
put some on cycles of 8 hrs lights on vs 16 off and vice versa for the others
52. While light stimulates tells small-headed animals whether it is day
or night, how is the pineal informed about the light-dark cycle in people?
input from the suprachiasmatic nucleus
53. Give one of the two possible reasons a diet high in tryptophan might
make you sleepy.
precursor to serotonin and to melatonin
54. "Reuptake into the nerve terminus terminates the synaptic action
of glutamate." How else is glutamate's action terminated?
it is also taken up into glia
55. What is sent throughout the brain from the Raphe nucleus?
56. A symptom of Parkinson's disease is bradykinesia. What is bradykinesia?
not moving much
57. Explain either (1) why schizophrenia was once attributed to a serotonin
defect, or (2) why this hypothesis was later excluded.
an LSD trip seemed like psychosis and LSD affected serotonergic transmission,
bur amphetamine induced psychosis was more similar to schizophrenia
58. How did your professor rationalize that action potentials would be smaller
in manic-depression patients who are on lithium therapy?
the gradient of lithium plus sodium, seen by the channel, would not be as
steep because the pump cannot pump lithium
59. Phosphatidylinositol and phosphatidylethanolamine, precursors for endogenous
cannabinoids, are supplied from what compartment in the cell?
60. What is in the tail of Torpedo that made it useful for cloners interested
in the nervous system?
lots of tissue with acetylcholine receptors
61. Why do you need to be very careful when you use muscle relaxation in
conjunction with anesthesia?
while it is important for your patient or your research animal not to move,
you must not paralyse without blocking pain
62. There is a muscle disorder where miniature end plate potentials are
smaller than they should be, and it is not because the vesicles do not have
enough acetylcholine. Answer either (1) What is the disorder? or (2) Why
are the potentials smaller?
myasthenia gravis, fewer nicotinic receptors
63. Why would you give someone a beta blocker?
to decrease blood pressure at the level of beta adrenergic receptors in
64. Phospholipase C converts a membrane phospholipid into (name or abbreviate
one of the two).
IP3 or DAG
65. Why is caffeine an "upper?"
norepinephrine and epinephrine action is potentiated since the second messenger's
breakdown by cAMP phosphodiesterase is inhibited